Composition comprising 7{60 -methyl estradiol 3,17-bistrimethyl silyl ethers

ABSTRACT

D R A W I N G

United States Patent 72] Inventors John C.Babcock;

J. Allen Campbell, both of Kalamazoo,

Mich. 211 AppLNo. 666,490 221 Filed Sept. 8, 1967 [45] Patented Dec. 7,1971

[73] Assignee The Upjohn Company Kalamazoo, Mich. Continuation-impart of application Ser. No. 114,621, June 5, 1961, now Patent No. 3,341,557, which is a continuation-in-part of application Ser. No. 69,557, Nov. 6, 1960, now abandoned. This application Sept. 8, 1967, Ser. No. 666,490

[54] COMPOSITION COMPRISlNG 7 a-METHYL ESTRADIOL 3,17-B1STR1METHYL SILYL ETHERS Primary Examiner- Elbert L. Roberts Attorneys-willard L. Cheesman and John Kekich ABSTRACT: This invention relates to novel steroid compounds and processes for their preparation; more particularly to those compounds embraced by the formula (1 1) R O C H:

wherein R is selected from the group consisting of hydrogen the acyl radical of a hydrocarbon carboxylic acid containing from one through twelve carbon atoms, an alkyl radical containing from one through eight carbon atoms, tetrahydrofuranyl, tetrahydropyranyl, S-substituted tetrahydropyranyl, and a silyl radical of the formula wherein R R and R are selected from the group consisting of alkyl of one through six carbon atoms and phenyl and R is selected from the group consisting of hydrogen, the acyl radical of a hydrocarbon carboxylic acid containing from one through twelve carbon atoms, and

wherein R R R have the same meaning as above.

COMPOSITION COMPRISING 7 orMETI-IYL ESTRADIOL 3 l 7-BISTRIMETIIYL SILYL ETHERS CROSS REFERENCES TO RELATED APPLICATIONS This application is a continuation-in-part of application Ser. No. 114,62l, filed June 5, I961, now Pat. No. 3,34l,557 which is in turn a continuation-in-part of abandoned application Ser. No. 69,557, filed Nov. 6, 1960.

BRIEF SUMMARY OF THE INVENTION 7a-methylestradiol, embraced by formula II, above, can be prepared by several known methods described below.

1. By reduction of the l7-carbonyl group of 7a-methylestrone (I), e.g., with sodium borohydride at moderate (room) temperature, to yield 7a-methylestradiol (ll),

2. By fermentation of 7a-methyl-l9-nortestosterone with a micro-organism capable of introducing a double bond in the l(2)-or l(2)and 4(5)--positions of the steroid nucleus, e.g., Corynebacterium simplex, to yield 7a-methylestradiol (II).

3. By dehydrogenating 7a-methyl'l9-nortestosterone, e.g., by heating in the presence of a hydrogenation catalyst (e.g., palladium on charcoal) in a high boiling solvent such as pcymene, to give 7a-methylestradiol (II).

The 3-ethers of 7a-methylestradiol of formula II, above, can be prepared by reducing the 3-ethers of 7a-methylestrone, e. g., 3-methyl ether of 7a-methylestrone (I), the 3-cyclopentyl ether of 7a-methylestrone (l), the 3-tetrahydropyranyl ether of 7-methylestrone l), etc., in accordance with the procedure of (l), above, to yield the corresponding 3-ether of 7a methylestradiol (II). The 3-acylates of formula II can likewise be prepared by the reduction of a 7a-methylestrone 3-acylate (l) by the procedure of l above, to yield the corresponding 7a-methylestradiol 3-acylate (ll).

The 3-ethers of 7a-methylestradiol of formula Il, above, can also be prepared by the known methods described below.

I. By treating 7a-methylestradiol (II) in accordance with the procedures disclosed in British Pat. No. 909,662, i.e., with an alkyl (or cycloalkyl) halide and an alkali metal alkylate, preferably at reflux temperature, to give a 3-alkyl (or cycloalkyl) ether of 7a-methylestradiol (ll).

2. By treating 7a-methylestradiol (II) with an alkylating agent (e.g., a dialkylsulfate) in conventional manner, to give a 3-alkyl ether of 7a-methylestradiol (ll).

3. By treating 7a-methylestradiol l7-acylate (II) with a cyclic enol ether (e.g., dihydrofuran, dihydropyran, 5-hydroxymethyldihydropyran, S-carboxydihydropyran, etc.) at low temperature, preferably in the presence of an acidic catalyst (e.g., phosphorus oxychloride), to give the corresponding 3- ether (e.g., tetrahydrofuranyl, tetrahydropyranyl, S-hydroxymethyltetrahydropyranyl, etc.) of 7a-methylestradiol l7- acylate (ll).

4. By treating 7a-methylestradiol (II) with a diazoalkane (e.g., diazomethane, diazoethane, diazobutane, etc.) at ambient temperature in an inert solvent such as ether, ethylene glycol, dimethyl ether, etc., to give the corresponding 3-alkyl ether of 7a-methylestradiol (ll).

5. By treating 7a-methylestradiol (II) or 7a-methylestradiol l7-acylate with a disilazane of the formula 2.3.1. .3 NH wherein R R and R have the same meaning as above (e.g., hexamethyldisilazane, symmetrical diphenyltetramethyldisilazane, l-methyl- I l -dibutyl-3-phenyl-3,3- dimethyldisilazane, hexa-amyldisilazane, etc.) to yield a corresponding 3,l7-bissilyl ether of 7a-methylestradio1 (ll) ora 3-silyl ether of 7a-methylestradiol l7-acylate (ll).

The 3,17-diacylates of 7a-methylestradiol of formula II,

above, can be preparedby conventional procedures, e.g., by

treating 7a-methylestradiol (ll) with the appropriate organic carboxylic acid anhydride (or chloride) at moderate temperatures for a period of 2 to 20 hours in the presence of an esterification catalyst such as pyridine, to yield the corresponding 7a-methylestradiol 3, l 7-diacylate (ll).

The 3-monoacylatesof 7a-methylestradiol (II) are obtained by treating 7a-methylestradiol with the: appropriate carboxylic acid anhydride or chloride at low to moderate temperatures for a period of a few minutes to several hours in the presence of an esterification catalyst such as pyridine to yield the corresponding 7a-methylestradiol 3-acylate (ll). Preferably the amount of carboxylic acid anhydride or chloride'should be between about 1 and 3 equivalents of the amount of steroid employed.

The l7-monoacylates of 7a-methylestradiol (II) are ob tained by mild alkaline hydrolysis of a 7a-methylestradiol 3,17-diacylate (ll) using methods known in the art, e.g., hydrolysis with an alkali metal carbonate in aqueous alcohol at low to moderate temperatures, or by chromotography over basic alumina, e.g., grade II, to obtain the corresponding 70:- methylestradiol 17-acylate (II).

The l7-acylates of formula II, above, can be prepared by conventional procedures e.g., by treating the 3-alkyl (or cycloalkyl) ether of 7a-methylestradiol (II), the 3- tetrahydropyranyl ether of 7a-methylestradiol (II), the 3- tetrahydrofuranyl ether of 7a-methylestradiol (ll), the 3-silyl ether of 7a-methylestradiol (ll) and the 3-acylate of 7amethylestradiol (II) with an acyl halide or anhydride in pyridine.

The 7a-methylestrone (I) starting material of (l), above, can be prepared by several known methods described below.

1. By fermentation of 7a-methyl-l9-nortestosterone or 7amethyl-l9-nor-4-androstene'3,l7-dione, with a micro-organism or its enzymes capable of introducing a double bond in the 1(2): o r ](2) and 4(5)-positio ns of the steroid nucleus, e.g., Cornyebacterium simplex or Septomyxa ajfinis to yield 70:- methylestrone (l).

2. By catalytically dehydrogenating 7a-methyll 9-nor-4-an drostene-3,l7-dione at the l(2)-positions, e.g., by heating in the presence of a hydrogenation catalyst (e.g., palladium on charcoal) in a high boiling solvent e.g., p-cymene), to give 7amethylestrone (l).

3. By treating 7a-methyl-l9-nor-4-androstene-3,l7-dione with a chemical dehydrogenating agent, e.g., a quinone such as 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ) or 2,3,5,6- tetrachloro-l,4-benzoquinone (chloranil), or selenium compounds such as selenium dioxide or dibenzoyloxy selenium oxide, to yield 7a-methylestrone (I).

4. By pyrolysis of 7a-methyl-l,4-androstadiene-3,l7-dione at elevated temperatures (e.g., between about 400 to 600 C.) its high boiling diluents (e.g., heavy mineral oil) to give 7a-methylestrone (l).

5. By treating 7a-methyl-l,4-androstadiene-3,l7-dione in accordance with the procedures described in J. Amer. Chem. Soc. 86, 742, Le, with lithium and diphenyl in the presence of diphenylmethane and employing tetrahydrofuran as solvent, to yield 7a-methylestrone (I).

The 3-ethers of 7a-methylestrone of formula I, above, can be prepared by the known methods described above for the preparation of the 3-ethers of 7a-methyllestradiol (ll) and 7amethylestradiol l7-acylates (II) from 7a-methylestradiol (II) and 7a-methylestradiol l7-acylates (ll).

The 3-acylates of 7amethylestrone can be prepared by conventional procedures, e.g., by treating 7a-methylestrone (l) with the appropriate organic carboxylic acid anhydride (or chloride) at moderate temperatures in the presence of an esterification catalyst such as pyridine, to yield the corresponding 7a-methylestrone 3-acylate (Il).

All of the compounds included within formulas l and II, above, can be isolated from their respective reaction mixtures by conventional means, for example, when a water-miscible solvent is used, by pouring the reaction mixture into water and separating the resulting precipitate by filtration or by extraction with water-immiscible solvents. Additional purification of the products can be accomplished by conventional means, for

example, by elution chromatography from an adsorbent column with a suitable solvent such as acetone, methanol, dilute methanol, ethanol, ether, methylene chloride and Skellysolve B (hexanes), mixtures and combinations of these solvents; also by gradient elution chromatography from an adsorbent column with suitable solvents, such as, Skellysolve B, methylene chloride-Skellysolve B, acetone-Skellysolve B, and the like.

The compounds of formula II of the present invention are potent estrogens when administered either orally or parenterally; when assayed in rats by the Allen-Doisy test 70:- methylestradiol was found to have approximately three times the activity of estradiol. In addition, the compounds of formula II, when combined with progestins such as 6a-methyl-l7ahydroxyprogesterone l7-acetate (Provera), 7a-methyl-17aethynyll 9-nortestosterone, l 7a-hydroxy-6-methyl-16- methylene-4,6-pregnadiene-3,20-dione 17-acetate (Melengestrol acetate), 17-hydroxyl 9-norl 7a-pregn-5( l )-en-20- yn-3-one (Norethynodrel l9-nor-17a-pregn-4-en-20-yne-3 B,17-diol-diacetate (Ethynodiol diacetate), 17 hydroxy-l9- nor-l7a-pregn-4-en-20-yn-3-one (Norethindrone), the corresponding 17-acetate (Norethindrone acetate), 601,21- dimethyl- 1 7fl-hydroxy-4-pregnen-20-yn-3one (Dimethisterone), 6-chloro-l 7a-hydr0xy-4,6-pregnadiene- 3,20-dione l7-acetate, etc., are useful for the prevention of ovulation in mammals. The foregoing properties make the new compounds useful in veterinary practice.

The compounds of the invention can be prepared and administered to mammals, birds and other animals, in a wide variety of oral or parenteral dosage forms, singly or in admixture with other coacting compounds. They can be administered with a pharmaceutical carrier which can be a solid material or a liquid in which the compound is dissolved, dispersed or suspended. The solid compositions can take the form of tablets, powders, capsules, pills, or the like, preferably in unit dosage forms for simple administration or precise dosages. The liquid compositions can take the form of solutions, emulsions, suspensions, syrups, or elixirs.

DETAILED DESCRIPTION It is to be understood that the invention is not to be limited to the exact details of operation or exact compositions shown and described herein, as obvious modifications and equivalents will be apparent to one skilled in the art, and the invention is therefore to be limited only by the scope of the appended claims.

EXAMPLE 1 7a-methylestrone(7a-methyl-1,3,5( 10)-estratrien-3ol-17- one) I) To 10 l. of sterile glucose-yeast extract medium there was added an inoculum of 500 ml. of Corynebacrerium simplex ATCC 6946. The culture was stirred and aerated for about 48 hours at a temperature of about 28 C., lard oil being added to suppress the foam. After about 48 hours the pH was 6.1. To the fermentor, 1 g. of 7a-methyl-l9-nortestosterone, prepared as in Steroids 1, 317, was added and aeration continued for about 24 hours. At this time the pH was 6.5. The beer was adjusted to pH 3 with hydrochloric acid and extracted four times with 3 l. of methylene chloride. Paper chromatography of an aliquot of the solvent extract indicated, by the Bush B-3 system, that essentially all of the 7a-methyl-l9-nortestosterone (I) had been reacted and that two compounds showing the characteristics of aromatic A ring steroids were present. The less polar compound had the mobility of 70: methylestrone (I) and the more polar that of 7a-methylestradiol (II). The methylene chloride extracts were evaporated to dryness and the residues obtained used for isolating the fermentation products. The crude residue was dissolved in methylene chloride and chromatographed through a 150 g. Florisil (synthetic magnesium silicated) column packed wet with Skellysolve B-hexanes) and eluted in 400 ml. fractions by gradient elution between 5 l. of 4 percent acetone-Skellysolve B and 5 l. of 12 percent acetone-Skellysolve B. Fractions 4 through 7 gave well-formed crystals. These fractions were combined and recrystallized from methanol with Darco (activated charcoal) treatment to give 5215 g. of 7a-methy1estrone (I), melting at 237 to 238 C. )tma'x. 280 mp; F2,10O.

Anal. Calcd. for C H OQ: C. 80.21; H, 8.51 Found: C. 80.10; H, 8.34

7a-methylestradiol (II) can be isolated from the more polar fractions.

EXAMPLE 2 7a-methylestrone (I) A sterile medium was prepared containing 10 l. of tap water, g. of cornsteep liquors and 100 g. of commercial dextrose and adjusted to pH 5 with sodium hydroxide. This was inoculated with 500 ml. of vegetative growth of Septomyxa afflnis (ATCC 6737) grown on the same medium. The culture was stirred and aerated at a rate of 0.1 l./minute. At the end of about 24 hours the pH was 7. To the fermentor, 2 g. of 7a-methyl-19-nortestosterone and 0.1 g. of 3-ketobisnor-4- cholen-22al dissolved in 20 ml. of N,N-dimethylformamide was added. Aeration was continued for about 48 hours, the pH adjusted to 3 and the beer extracted four times with methylene chloride. Paper chromatography indicated the presence of 7amethylestrone (I) in the extract. The product (I) can be isolated in accordance with the procedure described in example I to give essentially pure 7a-methylestrone (I).

Following the procedure of examples 1 and 2 but substituting 7a-methyll 9-nor-4-androstene-3, l 7-dione for 7a-methyl- 19-nortestosterone also yields 7a-methylestrone (I).

EXAMPLE 3 7a-methylestrone (I) A mixture of mg. of 7a-methyl-l9-nor-4-androstene- 3,17-dione, 40 mg. of 5 percent palladium on charcoal catalyst in 100 ml. of p-cymene (purified by passing through a column of alumina) was refluxed for about 1.5 hours. The catalyst was removed by filtration and the filtrate concentrated in a rotary evaporator. The residue was crystallized from ether to give 25 mg. of 7a-methylestrone (I), melting at 218 to 230 C., x1555. 279 mu, s=2,l50. Infrared spectral analysis indicates it is the same compound as prepared in examples 1 and 2. The product can be further purified by recrystallization or chromatography to give essentially pure 7a-methylestrone (II).

EXAMPLE 4 7a-methylestrone (I) To a solution of 100 mg. of 7a-methyl-19-nor-4-androstene- 3,17-dione, 100 mg. of 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ) and 0.5 ml. of acetic acid in 3 ml. of dioxane, 2 drops of 2.8 N hydrochloric acid solution in dioxane was added. After standing for about 16 hours, methylene chloride was added to the mixture and the solids filtered off. The filtrate was dried and the solvent removed. The residue, weighing about 30 mg., was triturated with methanol to give about 1 mg. of 7a-methylestrone (l) with xi'lx. 280 my, 2,350. Infrared analysis indicated that the thus produced compound is the same as those prepared in examples 1, 2 and 3.

Following the procedure of example 4, but substituting selenium dioxide or tetrachloro-p-benzoquinone (chloranil) for DDQ, also yields 7a-methylestrone (I).

EXAMPLE 5 A pyrolysis tube (18 inch X 1 inch) equipped with thermocouples about 3 inches from each end and packed with glass tubing cut in about 1/4-inch lengths was heated to about 550 C. and heavy mineral oil passed through at a rate of 5 ml./minute until constant temperature of 500 to 510 C. at the top and 540 to 560 C. at the bottom was obtained. A mixture of 10.4 g. of 7a-methyl-l,4-androstadiene-3,l7-dione and 500 ml. of heavy mineral oil mixed in a Waring blender was added at a rate of 5 ml./minute, maintaining the above temperatures. The effluent was refrigerated for several hours and the crystalline precipitate collected, washed thoroughly with Skellysolve B and dried to give 6.7 g. of crude 7amethylestrone (1). It was dissolved hot methylene chloride, cooled and poured on a 350 g. Florisil column packed wet with Skellysolve B and eluted with 400 ml. fractions by gradient elution between 5 l. of 4 percent acetone-Skellysolve B and 5 l. of 12 percent acetone-Skellysolve B. The desired product was contained in fractions through 21. The residues obtained from these fractions were combined and recrystallized from methanol to give 3.75 g. of 7a-methylestrone (I), having a melting point of230 to 235 C.; [a],,+140 (chloroform); xmfix. 279 mu; e=2,250. Nuclear magnetic resonance (NMR) spectra confirm the proposed structure and infrared spectral analysis shows it is the same as the product obtained in examples 1, 2, 3 and 4.

EXAMPLE 6 7a-methylestrone (l) Treating 7a-methyl-l,4-androstadiene-3,l7-dione in accordance with the procedures described in J. Amer. Chem. Soc. 86, 742, namely with lithium and diphenyl in the presence of diphenyl methane and employing tetrahydrofuran as solvent, yields 7a-methylestrone (1).

EXAMPLE 7 7a-methylestrone 3-cyclopentyl ether (1) A mixture of 1 g. of 7a-methy1estrone (l) and l g. of cyclopentyl bromide is added slowly to a solution of sodium ethylate (prepared from 0.1 g. of sodium and 8 ml. of absolute ethanol). The reaction mixture is heated to'reflux for about 4 hours, the ethanol removed by distillation and the residue treated with a small amount of water. A precipitate of 7amethylestrone 3-cyclopentyl ether (1) is obtained which is crystallized from a mixture of methylene chloride and methanol.

EXAMPLE 8 7a-methylestrone 3-methyl ether (1) To 4 g. of 7a-methylestrone (l) in a solution containing 6.4 g. of potassium hydroxide, 14 ml. of water and 21 ml. of methanol, 14 ml. of dimethyl sulfate was added dropwise with stirring and cooling sufficient to keep the reaction temperature at 25 to 35 C. At the same time a solution of 14 g. of potassium hydroxide in 28 ml. ofwater and 42 ml. ofmethanol was added dropwise at a rate that kept the pH of the reaction mixture about 10. The addition of the dimethylsulfate required about 30 minutes and the addition of the potassium hydroxide solution about 1 hour. The reaction mixture was stirred an additional 1.5 hours. Water was added and crystalline product collected on a filter, washed with water and dried to yield 3.8 g. of product (1) melting at 155 to 163 C. It was recrystallized from methanol to give an analytical sample of 7a-methylestrone 3-methyl ether (1) melting point 163 to 165; nag; 276 my; =2,100; x515 286 mu; t==2,050.

Anal. Calcd for CHI-12802: C, 79.95; H, 9.39. Found: C, 80.28; H, 9.48.

Following the procedure of example 8 but substituting for dimethylsulfate the following:

1. diethylsulfate,

dipropylsulfate, 3. diisopropylsulfate, 4. dibutylsulfate, 5. di-s-butylsulfate, 6. dipentylsulfate, 7. dihexylsulfate, 8. diheptylsulfate and 9. dioctylsulfate, yields, respectively, 1. 7a-methylestrone 3-ethyl ether l), 2. 7a-methylestrone 3-propyl ether l), 3

. 7a-methylestrone 3-isopropyl ether (1), 7a-methylestrone 3-buty1 ether (1 )1,

. 7a-methylestrone 3-s-butyl ether (1),

. 7a-methylestrone 3-pentyl ether (1),

. 7a-methylestrone 3-hexyl ether (1)),

. 7a-methylestrone 3-heptyl ether (1) and 7a-methylestrone 3-octyl ether (1).

EXAMPLE 9 7a-methylestrone 3-tetrahydropyranyl ether 1) To a solution of 4 g. of 7a-methylestrone (l) in 40 ml. of tetrahydrofuran (purified by percolation through a column of alumina) and 8 ml. of freshly distilled dihydropyran, 0.4 ml. of phosphorus oxychloride was added dropwise with stirring under nitrogen and cooling in an ice bath. After the addition was completed the ice bath was removed and after an additional 15 minutes the reaction mixture was poured into a mixture of saturated solution of sodium bicarbonate, ether and ice. The ether layer was separated, washed with dilute sodium bicarbonate solution, water, dried over sodium sulfate and filtered. The filtrate was evaporated to dryness to give 5.1 g. of 7a-methylestrone 3-tetrahydropyranyl ether (1).

Following the procedure of example 9 but substituting for dihydropyran the following:

1. dihydrofuran, 2. 5-hydroxymethy1dihydropyran, 3. S-carboxydihydropyran, etc., yields, respectively, 1. 7a-methylestrone 3-tetrahydrofuranyl ether (l), 2. 7a-methylestrone 3-(5-hydroxymethyl) tetrahydropyranyl ether (1), 3. 7a-methylestrone 3-(5-carboxy) tetrahydropyranyl ether (1), etc.

EXAMPLE l0 7a-methylestrone 3-acetate (1) To 1 g. of 7a-methylestrone (l), 2 ml. of pyridine and 1 ml. of acetic anhydride is added. The reaction mixture is kept at room temperature for about 3 hours; water is then added to precipitate the product (I) and destroy the excess acetic anhydride. Recrystallization from acetone and Skellysolve B yields 7a-methylestrone 3-acetate (1).

Following the procedure of example but substituting for acetic anhydride (and allowing additional time for the slower reacting anhydrides) the following:

. benzoic acid anhydride,

propionic anhydride,

butyryl chloride,

i-valeryl chloride,

decanoyl chloride,

hexanoic anhydride,

sec. octanoic anhydride capric anhydride,

undecyl anhydride,

10. dodecanoyl chloride, etc., yields, respectively, 1. 7a-methylestrone 3-benzoate (l), 2. 7a-methylestrone 3-propionate (l), 3. 7a-methylestrone 3-butyrate (l), 4. 7a-methylestrone 3-i-valerate (l),

5. 7a-methylestrone 3-decanoate (l),

6. 7a-methylestrone 3-hexanoate (l),

7. 7a-methylestrone 3-sec. octanoate (l),

8. 7a-methylestrone 3-caproate (I),

9. 7a-methylestrone 3-undecanoate (l),

l0. 7a-methylestrone 3-dodecanoate (1), etc.

EXAMPLE 1 l 7a-methylestrone 3-trimethylsilyl ether (I) To a suspension of 4 g. of 7a-methylestrone (I) in 10 ml. of dry acetone, 6.5 m1. of hexamethyldisilazane was added. The mixture was stirred for about 4 days and then evaporated to dryness. The residue was dissolved in a mixture of methylene chloride and Skellysolve B and chromatographed over a 250 g. column of Florisil. Gradient elution between l. of Skellysolve B and 5 l. of percent acetone-90 percent Skellysolve. B yielded 2.5 g. of 7a-methylestrone 3-trimethylsilyl ether (ll) having a melting point of 103 to 107 C.

Following the procedure of example ll but substituting other disilizanes for hexamethyldisilizane, such as symmetrical diphenyltetramethyldisilazane, hexaamyldisilazane, etc., yields, respectively, 7a-methylestrone 3-phenyldimethylsilyl ether (1 7a-methylestrone 3-triamylsilyl ether (l), etc.

The reactions of example 1 l and the paragraph thereafter are preferably carried out with the addition of a few drops to 2 ml. of trimethylsilyl chloride.

In place of acetone in example I 1, other inert dry solvents, such as tetrahydrofuran, dioxane, methylene chloride and the like, can be utilized.

EXAMPLE l2 7a-methylestradiol (ll) To a solution of 100 mg. of 7a-methylestrone (l) in 5 ml. of methanol, one drop of water and 40 mg. of sodium borohydride was added. After about minutes a small additional amount of sodium borohydride was added. After several more minutes excess sodium borohydride was destroyed with a few drops of acetic acid. Water was added and the solution neutralized with 2 N hydrochloric acid. The crystalline residue was collected, washed with water and recrystallized from aqueous methanol. After several days of drying at 75 C. the compound, 7a-methylestradiol (ll), melted at 157 to 161 C.; Amzi'x. 281 uu; e=2,l00. lts infrared absorption spectrum supports the structure proposed for it.

Anal. Calcd. for CnHzuOzZ C, 79.67; H, 9.l5. Found: C, 79.37; H, 9.2l.

UIbWN MANN- EXAMPLE l3 7wmethylestradiol (11) A mixture of lOO mg. of 7a-methyl-l9-nortestosterone, 40 mg. of catalyst (5 percent palladium on activated charcoal) in l00 ml. of p-cymene (purified by passing through a column of alumina) was refluxed for about 1.5 hours. The catalyst was removed by filtration and the filtrate concentrated to dryness to give 7a-methylestradiol (ll). The product may be further purified by chromatography and recrystallization.

EXAMPLE l4 7a-methylestradiol l 7-acetate (ll) Following the procedure of example l3, but employing 7amethyl-l9-nortestosterone l7-acetate as starting material, yields 7a-methylestradiol l7-acetate (ll).

Following the procedure of example l4, but substituting for 7a-methyll 9-nortestosterone l7-acetate other 7a-methyll 9- nortestosterone l7-acylates, such as the l7-propionate, l7- butyrate, l7-i-valerate, l7-sec. octanoate, 17-dodecanoate, etc., yields the corresponding 7a-methylestradiol l7-acylate (ll).

EXAMPLE l5 7a-methylestradiol 3-methyl ether (ll) Following the procedure of example 8, but substituting 7amethylestradiol (ll) for 7a-methylestrone (l) as starting material, is production of the 3-methyl ether of 7amethylestradiol (ll).

Similarly, following the procedure of example 8, but substituting for 7a-methylestrone (I) as starting material 701- methylestradiol and substituting for dimethylsulfate the fol- EXAMPLE l6 7a-methylestradiol l7-acetate 3-trimethylsilyl ether (II) To a suspension of 4 g. of 7a-methylestradiol 17-acetate (ll) in 10 ml. of dry acetone, 6.5 ml. of hexamethyldisilazane is added. The mixture is stirred for about 4 days and then evaporated to dryness. The residue is dissolved in a mixture of methylene chloride and Skellysolve B and chromatographed over a 200 g. column of Florisil. The product is eluted by gradient elution between Skellysolve B and 10 percent acetone in Skellysolve B to give 7a-methylestradiol l7- acetate, I i-trimethylsilyl ether (ll).

Following the procedure of example 16 but substituting other disilazanes for hexamethyldisilazine, such as symmetrical diphenyltetramethyldisilazane, hexaamyldisilazane, etc., yields, respectively, 7a-methylestradiol l7-acetate, 3-phenyldimethylsilyl ether (ll), 7a-methylestradi0l l7-acetate, 3-triamylsilyl ether (ll), etc.

The reactions of example 16 and the paragraph thereafter are preferably carried out with the addition of a few drops to 2 ml. of trimethylsilyl chloride.

in place of acetone in example 16, other inert dry solvents, such as tetrahydrofuran, dioxane, methylene chloride and the like, can be utilized.

Substituting other 7a-methylestradiol l7-acylates (ll) for 7a-methylestradiol l7-acetate (ll) and the procedure of example 16 is productive of other 7a-methylestradiol l7- acylate, S-trimethylsilyl ethers (ll).

Substituting 7a-methylestradiol (II) for 760 -methylestradiol l7-acetate (II) in the procedure of example 16 is EXAMPLE I? 7a-rnethylestradiol 3, l 7-diacetate (ll) Following the procedure of example 10, but substituting 7amethylestradiol (ll) for 7a-methylestrone (l) as starting material yields 7a-methylestradiol 3,l7-diacetate (ll). Additionally, substituting the acid anhydrides named following example l for acetic anhydride yields the corresponding 3,17- diacylates, respectively,

. 7a-methylestradiol 3,17dibenzoate (ll),

. 7a-methylestradiol 3,17-dipropionate (ll),

. 7a-methylestradiol 3,17-dibutyrate (ll),

. 7a-methylestradiol 3, l 7-divalerate (ll),

. 7a-methylestradiol 3,17-didecanoate (ll),

. 7a-methylestradiol 3,17-dihexanoate (ll),

. 7a-methylestradiol 3 l 7-disecondaryoctanoate ll), 7a-methylestradiol 3,17-dicaproate (ll),

9. 760 -methylestradiol 3, l 7-diundecanoate (ll l0. 7a-methylestradiol 3,17-didodecanoate (ll), etc.

Substituting 7a-methylestradiol 3-acylates (II) for 7amethylestradiol (ll) in the procedure of example 17 is productive of 7a-methylestradiol 3,17-diacylates (ll) in which the two acylate groups can be the same or different.

Substituting 7a-methylestradiol 3-methyl ether (ll) 70:- methylestradiol 3-cyclopentyl ether (ll) other 7a-methylestradiol 3-ethers (ll), 7a-methylestradiol 3-tetrahydropyranyl ether (ll), 7a-methylestradiol 3-tetrahydrofuranyl ether (ll), 7a-methylestradiol 3-trimethylsilyl ether (ll), other 7amethylestradiol 3-silyl ethers, and the like for 7a-methylestradiol (ll) in the procedure of example 17 affords the corresponding l7-monoacylate (Il), e.g., 7a-methylestradiol 3- methyl ether l7-propionate (ll), 7amethylestradiol 3- cyclopentyl ether l7-acetate (ll), 7a-methylestradiol 3- tetrahydropyranyl ether l7-acetate (ll), 7a-methylestradiol 3- tetrahydrofuranyl ether I7-acetate (ll), 7a-methylestradiol 3- trimethylsilyl ether l7-decanoate (II) and the like.

EXAMPLE l8 7a-methylestradiol l7-trimethylsilyl ether (II) In a solution of 1 g. of 7a-methylestradiol 3-acetate l7- trimethylsilyl ether (ll) in 30 ml. of isopropyl alcohol, l0 ml. of water containing 500 mg. of sodium bicarbonate is added. The mixture is allowed to stand for one-half hour and is then evaporated at room temperature under vacuum. Methylene chloride and water are added and the organic phase separated and washed several times with water. The solvent is evaporated to afford 7a-methylestradiol l7-trimethylsilyl ether (II). The product is purified, if desired, by chromatography over neutral alumina to give essentially pure 7amethylestradiol l7-trimethylsily ether (ll).

Substituting other l7-silyl ethers of 7a-methylestradiol 3- acetate (ll) (e.g., the l7-triamylsilyl ether) in the procedure of example 18 is productive of the corresponding 7a-methylestradiol l7-silyl ether (ll).

As indicated above, the compounds of this invention are useful for their estrogenic activity in mammals. Dosage depends on the particular compound involved, route of administration, severity of the condition being treated and the individual's response thereto. In general, a dose of between about 0.01 mg. to about mgs. of each of the compounds exemplified in examples 12 through [8 and embraced within formula II is given orally once a day, or subcutaneously or in tramusculary in a dose of 0.05 to 10 mg. weekly to monthly in the treatment of conditions incident to the foregoing activity when incorporated in conventional pharmaceutical compositions.

The following examples illustrate the incorporation of the active ingredients of this invention in pharmaceutical formulation for use as estrogenics.

EXAMPLE l9 Compressed tablets A lot of 10,000 compressed tablets, each containing 0.05 mg. of 7a-methylestradiol or 7a-methylestradiol 3methyl ether is prepared from the following ingredients:

7u-methylestradiol or la-methylestrudiol B-methyl ether 0.5 g. Dicalcium phosphate 2500 g. Methylcellulose. USP l5 cps.) 65 g. Tulc, bolted 450 g. Calcium stearate. fine powder 35 g.

The 7a-methylestradiol or 7a-methylestradiol 3-methyl ether and dicalcium phosphate are mixed well, granulated with 7.5 percent solution of methylcellulose in water, passed through a No. 8 screen and dried at F. The dried granules are passed through a No. 12 screen, mixed thoroughly with the talc and and stearate and compressed into tablets.

EXAMPLE 20 Hard gelatin capsules A lot of 1000 hard gelatin capsules, each containing 0.5 mg. of 7a-methylestradiol or 7a-methylestradiol 3-methyl ether is prepared from the following ingredients:

7a-methylestradiol or 7a-methylestradiol 3-methyl ether 0.5 g. Lactose g. Calcium stearate 2 g. Tale 3 g.

The lactose, talc and stearate are mixed well and incorporated into the mixture. The whole is mixed well and filled into two-piece hard gelatin capsules.

EXAMPLE 21 Soft gelatin capsules A batch of 1000 soft gelatin capsules, each containing 0.5

mg. of 7a-methylestradiol or 7a-me'thylestradiol 3-methyl ether and corn oil is prepared from the following materials:

7u-melhylestradiol or 7a-methylestradiol 3-melhyl ether 0.5 g. Corn oil q.s.

A uniform dispersion of the active ingredient in the corn oil is prepared and the dispersion filled into soft gelatin capsules by conventional means.

EXAMPLE 22 Aqueous oral suspension An aqueous oral suspension containing in each 5 ml. 0.5 mg. of 7a-methylestradiol or 7a-methylestradiol 3-methyl ether is prepared from the following materials:

7n-methylestradiol or 7u-methylestradiol EXAMPLE 23 Aqueous suspension for injection A suspending vehicle is prepared from the following materials:

The parabens are added to a major portion of the water and are dissolved therein by stirring and heating to 65 C. The resulting solution is cooled to room temperature and the remainder of the ingredients are added and dissolved. The balance of the water to make up the required volume is then added and the solution sterilized by filtration. The sterile vehicle thus prepared is then mixed with 0.5 g. of 7a-methylestradiol or 7a-methylestradiol S-methyl ether which has been previously reduced to a particle size less than about 10 microns and sterilized with ethylene oxide gas. The mixture is passed through a sterilized colloid mill and filled under aseptic conditions into sterile containers which are then sealed.

Each milliliter of this suspension contains 0.5 mg. 701- methylestradiol or 7a-methylestradiol 3-methyl ether.

As indicated above, the compounds of this invention, in addition to their use as estrogenics, when combined with progestins, e.g., 6a-methyll 7a-hydroxyprogesterone l7- acetate (Provera 7a-methyll 7a-ethynyl l 9-nortestosterone, l7a-hydroxy-6-methyll 6-methylene-4,6-

pregnadiene-3,20-dione l7-acetate (Melengestrol acetate), etc., are useful for the prevention of ovulation in mammals. Administration to mammals depends on the particular progestin and estrogen involved and the individuals response thereto. In general, a dose of between about 0.01 mg. to about 5 mgs. of each of the estrogens exemplified in examples 12 through l8 and embraced within formula II plus between about 1 mg. to about 100 mgs. ofa progestin is given at such time(s) in the mammalian ovulatory cycle as is suitable for the prevention of ovulation.

The following examples illustrate the incorporation of the active ingredients of this invention with progestins in pharmaceutical formulation for use as anovulatory agents.

EXAMPLE 24 Oral tablets 50,000 tablets for oral administration are prepared from the following types and amounts of materials. Each tablet contains 3.0 mgs. of 6a-methyl-l7a-hydroxyprogesterone l7-acetate and 0.03 mg. of 7a-methylestradiol or 7a-methylestradiol 3- The finely powdered active ingredients and lactose are mixed well and granulated with syrup-starch paste. Starch and calcium stearate are used as lubricants in the compressing step.

EXAMPLE 25 Oral tablets 10,000 tablets for oral administration are prepared from the following types and amounts of ingredients. Each tablet contains l mgs. of 6a-methyl-l7a-hydroxyprogesterone 17- acetate and 0.05 mg. of 7a-methylestradiol or 7a-methylestradiol 3-methyl ether.

oa-methyll 7a-hydroxyprogesterone l7-ucetute 7a-methyleslradiol or 7a-methylestrudiol 3-methyl ether Lactose The finely powdered active ingredients and lactose are mixed well and granulated with syrup-starch paste. Starch talc. and calcium stearate are used as lubricants in the compressing step.

EXAMPLE 26 Oral aqueous suspension An aqueous suspension for oral administration, containing in each teaspoonful (approximately 5 mls.) 5 mgs. of 6amethyl-I7a-hydroxyprogesterone l7-acetate and 0.2 mg. of 7a-methyl-estradiol or 7a-methylestradiol 3-methyl ether is prepared from the following types and amounts of ingredients:

oamethyll 7a-hydroxyprogesterone l7-ncetate 7a-methylestradiol or 7a-methylcutradiol J-methyl ether Prcservative Flavor, q.s.

Purified water U.S.P.. u.s. ad 1000 mix.

The preservative and flavor are dissolved in the water. The micronized active ingredients are added and the whole is homogenized.

EXAMPLE 27 Oral gelatin capsules ba-methyll 7d-hydroxyprogcsterone l7-acetate l0 g. 7a-methylestradiol or 7a-methylestradiol J-methyl ether 50 mgs.

lngestible oil. q.s.

The micronized active ingredients and the oil are mixed and the mix is encapsulated by the usual techniques into gelatin capsules.

EXAMPLE 28 Oral tablets Following the procedure of example 24, 5000 tablets are prepared from the following types and amounts of ingredients. Each tablet:

5 mgs. 6a-methyll 7a-hydroxyprogesterone l7-ncetate 25 g. 0.0] mg. 7a-methylestradiol or 7a-methylestradiol J-methyl ether 50 mgs. I50 mgs. lactose 750 g. 3 mgs. acacia 15 g. 65 mgs. starch bolted 325 g. 3 mgs. calcium stearate l5 3.

Tablets equally suited for the inhibition of ovulation are prepared by using 250 and 1000 mgs., respectively, of the 7amethylestradiol or 7a-methylestradiol 3-methyl ether in place of the 50 mgs. in the above formulation.

While the procedure described above in examples 24 through 28 recite the use of the progestin 6a-methyl-l7ahydroxyprogesterone l7-acetate, other progestational com-i pounds can be substituted therefor the provide similarly effective anovulatory pharmaceutical formulations; e.g., 7amethyl-l 7a-ethynyll 9-nortestosterone, l7a-hydroxy-6- methyl- 1 6-methylene-4,6-pregnadiene-3,20-dione l7-acetate, l7-hydroxyl 9-norl 7a-pregn-5( l0)-en-20-yn-3-one, l 9norl7a-pregn-4-en-20-yne-3fl, l7-diol 3,17-diacetate, l7- hydroxyl 9-norl 7a-pregn-4-en-20-yn-3-one l7-acetate,

604,2 1 -dimethyll 7fl-hydroxy-4-pregnen-20-yn-3-one, 6- chlorol 7a-hydroxy-4,6-pregnadiene-3,20-dione l 7acetate, etc., can be employed instead of 6a-methyl-l7a-hydroxyprogesterone l7-acetate.

We claim:

l. 7amethylestradiol 3,17-bistrimethylsilyl ether having the formula 2. An oral pharmaceutical composition comprising: a. about 0.01 to about mg. ofa compound of the formula comprising: orally administering to ovulating mammals an effective amount of a. a compound of the formula wherein R is selected from the group consisting of hydrogen and methyl and R is hydrogen, and

b. a progestin.

5. A method of preventing ovulation in ovulating mammals in accordance with claim 4 wherein the progestin is methyl- 1 7a-ethynyl-l 9-nortestosterone. 

2. An oral pharmaceutical composition comprising: a. about 0.01 to about 5 mg. of a compound of the formula
 3. A composition in accordancd with claim 2 wherein the progestin is 7 Alpha -methyl-17 Alpha -ethynyl -19-nortestosterone.
 4. A method of preventing ovulation in ovulating mammals comprising: orally administering to ovulating mammals an effective amount of a. a compound of the formula
 5. A method of preventing ovulation in ovulating mammals in accordance with claim 4 wherein the progestin is 7 Alpha -methyl-17 Alpha -ethynyl-19-nor testosterone. 